Visitors to Argentina’s Patagonia coast witnessed something extraordinary this year, according to the Associated Press. A record number of southern right whales gathered off the Valdés Peninsula, with one tourist saying it was “the largest number of whales I’ve ever seen in my life.”

Once hunted to near extinction, southern right whales are now thriving again in these protected waters. The sheltered waters of the Valdés, located in the Patagonian province of Chubut, have long been vital breeding and nursery grounds for the whales as well as other species such as elephant seals and sea lions.

Whale sightings have more than quadrupled since the late 1990s to 2,100, and the actual number is likely even higher, the AP reported. In fact, researchers estimate that the population around Valdés has grown to roughly 4,700 whales, with 3% annual increases. This is especially encouraging because the southern right whale population was decimated in the last century by whaling, plummeting from 50,000-70,000 in the 1700s to a mere 300 by the 1920s, per the World Wildlife Fund.

Tourists from around the world visit El Doradillo and nearby viewing points to watch families of whales breaching just offshore.

“I’ve seen whales in Canada and California, but this was the best and probably the largest number of whales I’ve ever seen in my life,” said German Tino Ventz, who visited the peninsula with his partner.

Meanwhile, Agustina Guidolín told the AP that she fulfilled her dream of witnessing “the immensity that borders on the magical and the wild.”

“We’re underestimating the number of whales in the area,” said biologist Santiago Fernández, who helps with annual aerial surveys through Argentina’s National Scientific and Technical Research Council, noting that whales move outside the study zone.

Similar improvements have been documented elsewhere, from blue whales returning to the waters off the coast of Massachusetts to unexpected sightings of blue whales near Seychelles. Each of these cases shows how careful stewardship can help marine life rebound and thrive.

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